Glory holes are also common on construction sites, though not necessarily in the sexual form. A netizen by the name of shop_steward wrote:
In the western states during the Gold Rush days, independent miners who did not have the finances to dig a conventional mine shaft would dig a shaft staight down to try to find a gold seam. These perpendicular shafts became known as Glory Holes.
The name stuck and many construction projects involving digging are called "Glory Holes".
These can be seen all over Boston, due to the ongoing Big Dig project.